A top European Union official has threatened to sanction Panama and other nations if they don't cooperate to fight money laundering and tax evasion of the type seen in leaked documents this week.

The Panama-based law firm Mossack Fonseca helped thousands of rich and famous people as well as global corporations set up shell companies and offshore accounts to avoid taxes in their home states.

Because such accounts often hide the identity of the wealth holders, they are also used to launder money or pay bribes.

"People are fed up with these outrages," said Pierre Moscovici, who heads financial affairs for the 28-nation EU. "The amounts of money, the jurisdictions, and the names associated with this affair are frankly shocking."

Panama is listed by the EU as a country that is not cooperative on tax issues, and Moscovici urged the country to "rethink its position in this regard."

"Let's call a spade a spade: Noncooperative jurisdictions are tax havens," he said. The EU has to "be ready to hit them with appropriate sanctions if they refuse to change."